Definition
A ground-based system installed at the end of certain runways that physically stops or slows an aircraft that is unable to stop within the available runway length. Common types include engineered material arresting systems (EMAS), which use crushable concrete blocks that collapse under the aircraft's weight to absorb energy, and cable or net arresting systems used primarily at military airfields to engage a hook or capture the airframe.
Plain English
A safety system at the end of a runway that catches or slows an aircraft if it can't stop in time, helping prevent it from running off the runway into something worse.
Context Anchor
Pilots encounter this term when studying runway safety, airport diagrams, rejected takeoffs, landing overruns, and airport features intended to reduce damage after an aircraft leaves the runway surface.
Derivation
"Arrest" comes from the Latin restare, meaning "to stop" or "hold back." The device is named for what it does -- it arrests (stops) the aircraft's motion in an emergency.
Why Pilots Care
Provides a last-resort method to prevent runway excursions and reduce aircraft damage or injury risk.
Analogy
It is similar in idea to a runaway-truck ramp on a steep road: it gives a vehicle that cannot stop normally a prepared place to lose speed quickly.
Intuition Check
Do not read “arresting” as “attention-getting” or “police-related.” Here, “arresting” simply means stopping the aircraft in an emergency.
Example Sentence 1
After the brakes faded on landing, the aircraft rolled into the EMAS bed at the runway end, and the emergency arresting device brought it to a stop within about 200 feet.
Example Sentence 2
Airports install emergency arresting devices at runway ends to protect against excursions during rejected takeoffs.